When Paolo Nutini began the process of "reintroducing himself to the public" (his phrase) a couple of months ago, the first stop was, appropriately, Glasgow, where he was announced as one of the headliners at Radio 1's Big Weekend in May.

At the press conference at BBC Scotland's HQ, Pacific Quay, Nutini was subject to the now inevitable grilling about his voting intentions in the September referendum. The persistent questioner left without an answer.

However, a close listen to Nutini's new album, Caustic Love, out next week, may raise it again. The track Iron Sky, recorded at the studio in Ireland where the singer-songwriter's co-producer Dani Castelar is based, is the most political song he has recorded, and was one of the first to be made available online as a taster for the album.

As well as Nutini's impassioned vocals - one of the record's best examples of his mature soul voice - it includes a long sample of the famous speech Charlie Chaplin wrote for The Great Dictator, his satirical movie about the rise of Hitler, including the resonant lines: "You are not machine men, with machine minds."

After Nutini debuted the song in Berlin last month, where it obviously had particular resonance and was rapturously received, the delighted performer told me it was also where to find his views on the independence debate.

It will be interesting to discover how it is interpreted, because his plea for individual freedom and expression over all other imperatives is ambiguous. But to my ears its repetition of the word "freedom" is as much a reclaiming of it from the film Braveheart as any endorsement of the Yes camp, and the political machine Nutini wants to resist might as easily be nationalist as anything else.

If Iron Sky is a personal statement from Nutini, it is not alone on the new disc, which has been years and many sessions in the making. Its final form was arrived at so late in the day that different promotional versions of the disc were issued to the music press as extra tracks were finally completed and cleared legal hurdles for some of the elements they use.

The list of personnel includes some of the best drummers in the world, with the ubiquitous Seb Rochford from Aberdeen on many of them and the great funk drummer James Gadson on lead single Scream (Funk My Life Up) and the Janelle Monae-featuring Fashion, where much of the rhythm work was laid down at Sunset Sound in Los Angeles. There were other sessions in Valencia, Spain, and in Brighton and London.

A New Orleans-flavoured track about a relationship in trouble was known as Watch It Fall until shortly before the album was signed off, when it became the more colloquial "Numpty". It includes contributions from veteran bassist Pino Palladino and guitarist Chris Spedding, whose career include stints with Bryan Ferry and as a Womble.

"Titles are the least of my problems," said Nutini as he signed the new disc off. "Some of these tracks have been around for quite a while, but on some of the tunes it all came together at the end. I'm glad I waited. The album is down to me in the end. I have to live with it and let it go."

Cherry Blossom, the sole band composition, is one of the oldest, and the most out-and-out rocker on the disc, with Nutini's vocal performance recalling Eddie Vedder of Pearl Jam.

"It's one of the more sinister songs on the album," says Nutini. "It was only when we recorded it in Ireland with all the band on stage we unlocked that crescendo at the end."

It is immediately preceded on the final running order of Caustic Love by Looking For Something, Nutini's moving tribute to his mother, which found its form on the final night of three weeks of sessions, when bassist Michael McDaid supplied the riff that underpins Nutini's melody. "Only then could I focus in on the lyric," says Nutini, "because I didn't want anyone to tell me it wasn't good."

Guitarist Leo Abrahams, who has made his own experimental music for Glasgow-based Linn records, is another associate with a significant contribution to some of the bigger compositions on the set, which use strings as well as more brass. But the concluding little song, Someone Like You, survives from rehearsal sessions with Nutini's own portable studio set up in a disused police station in the Gorbals, and has the singer's original manager, Brendan Moon, on bass.

"In the end I decided it just didn't need anything else," says Nutini.

"A lot of musicians have had input into a good proportion of the songs, and it helps to have a producer to give you direction. There are ideas that I can't fully realise on my own - I am not as accomplished a musician as I should be. But I have learned how to approach the stage where I can acknowledge a record is being made and rise above the frustrations and uncertainties of the process, because they spark new ideas and new songs.

"In certain elements I can maybe be too single-minded, and I recognise my own stubbornness, but I can't help myself going and running with things. You have to move at your own pace."

Although the same single-minded young man will talk about "fulfilling his deal" with the record label and looking forward to "a new independent approach with less compromise", it is true he has had the good fortune to enjoy the sort of nurtured development that parallels that of the young Kate Bush.

It is also a far cry from the way young talent is now routinely used up and spat out by the "machine men with machine minds" though the medium of bovine TV.

"When no-one is telling you what to do, you can only do what feels right to you," says Nutini. And when an album as good as Caustic Love is the result, every one is a winner.

Paolo Nutini's Caustic Love is released on Atlantic Records on Monday.

Read Alan Morrison's review in the Sunday Herald this weekend.